利用生物反应器大量生产人参不定根

在5 L气球型生物反应器中,采用完全浸没式培养方式,人参不定根鲜重和干重明显优于间歇浸没式培养;在培养开始时一次性注入含50 g/L蔗糖的培养基,可促进人参不定根鲜重和干重的增加;接种时,将不定根切成1 cm长、接种量为20 g时接种较适宜;增殖培养周期以30天为宜.     

滚筒式生物反应器固态发酵的应用研究

传统方法生产丹贝（大豆发酵食品）都以静态方式进行固态发酵，发酵过程中热质传递受到一定的限制，会产生温度梯度，且气体组分不均匀，从而导致发酵产品质量不稳定。滚筒式生物反应器的应用可以促进热质传递，使物料均匀发酵，且易于实现机械化生产和扩大生产规模。笔者参予设计制造了450L的滚筒式生物反应器，并利用其进行了固态发酵生产丹贝的应用研究。以2株根霉为发酵剂，进行了静态和动态固态发酵的对照试验，并对发酵过程中物料的化学组分和微生物组成进行了检测。结果表明，滚筒式固态发酵产品质量可靠；不同的菌株对搅动有不同的反应，其中微孢子根霉对搅动有适应能力，适用于滚筒固态发酵。     

蓝藻厌氧发酵控制因素与反应器应用研究进展

蓝藻厌氧发酵生产沼气是蓝藻资源化利用的一个重要方式。综述了蓝藻厌氧发酵产沼过程的控制因素和厌氧反应器的应用,为从工程上实现蓝藻发酵制沼气提供参考。     

家禽的转基因技术研究

转基因技术的研究虽然备受争议,但是由于具有广阔的应用前景,近年来发展十分迅速。与哺乳动物相比,禽类具有特殊的生殖系统,因此家禽的转基因研究相对较为滞后。影响转基因家禽研制的关键因素在于表达载体的选择和外源基因的导入方式,这决定了如何获得较高的孵化率和转染率。笔者对目前用于转基因家禽制备的常用载体、转基因家禽制备的方法以及转基因鸡的后续孵化技术进行了综述。     

油体蛋白与人成骨蛋白-1基因融合植物表达载体的构建及融合蛋白性质预测

克隆大豆油体蛋白特异启动子及油体蛋白基因的全长序列,利用连接PCR的方法,通过一个肠肽酶位点将人成骨蛋白成熟肽编码序列连接到油体蛋白基因3'端并克隆到表达载体pCAMBIA1302中,构建"油体蛋白-肠肽酶-人成骨蛋白"植物表达载体.通过酶切、PCR和测序鉴定,证明表达载体构建成功,将其命名为pCAM-oleo-Bmp7.通过蛋白分析软件DNAstar、SignalP3.0和ProtComp v8.0等软件对重组蛋白的理化性质、二级结构、信号肽和细胞定位进行了分析和预测,证明融合蛋白很好的保留了原来两个蛋白的二级结构和理化性质.     

Effects of growth factors on equine synovial fibroblasts seeded on synthetic scaffolds for avascular meniscal tissue engineering

Across species, the avascular portion of the knee meniscus cannot heal spontaneously if severely injured. The most common treatment is meniscectomy which results in osteoarthritis. The objective of this study was to assess the fibrochondrogenic potential of equine fibroblast-like synoviocytes (FLS) seeded on scaffolds under the influence of growth factors in vitro to determine the potential of developing a novel cell-based repair strategy. Cultured FLS were seeded onto synthetic scaffolds in a rotating bioreactor under the influence of three growth factor regimens: none, basic fibroblast growth factor (bFGF) alone, and bFGF plus transforming growth factor (TGF-β₁) and insulin-like growth factor (IGF-1). Constructs were analyzed for mRNA expression and production of fibrochondroid extracellular matrix constituents. Type II collagen and aggrecan mRNA were significantly higher in growth factor-treated groups (p < 0.05). Despite sub-optimal extracellular matrix production, FLS can exhibit fibrochondral characteristics and may have potential for cell-based tissue engineering for avascular meniscal regeneration.     

大熊猫犬瘟热病毒（CDV-PA-1421株）微载体悬浮培养工艺研究

根据正交试验对大熊猫犬瘟热病毒(CDV-PA-1421株)在生物反应器中的培养工艺进行优化，确定关键技术参数。结果表明，大熊猫犬瘟热病毒悬浮培养最佳组合条件为：Vero细胞长成单层后，接种到生物反应器，细胞接种浓度为0.2×10⁶/mL~0.4×10⁶/mL，微载体浓度为8.0 g/L，加入MSVP培养基至工作体积。按0.01～0.1 感染复数(MOI)接种病毒，在37 ℃ pH7.2条件下培养96~120 h，细胞病变(CPE)达70%～80%时收获病毒上清液，即可获得高滴度病毒液。3批培养结果显示病毒培养工艺稳定，收获液病毒含量均在10^7.0～10^7.5 TCID50/0.1mL之间。     

叶绿体基因工程在农业中的应用

叶绿体转基因工程与核转基因相比具有明显的优越性,包括:外源基因的高效表达,基因的原核表达形式,无位置效应和基因沉默现象,环境安全性好。目前已经有许多作物品种通过叶绿体基因工程获得了抗除草剂、抗虫、抗病、耐盐耐旱的特性。叶绿体转基因植物是作为生物反应器的理想系统。但是叶绿体转基因也面临着许多挑战,如转化效率低、单子叶植物再生系统的确立与筛选以及叶绿体基因组序列的获得。     

A novel approach to denitrification processes in a zero-discharge recirculating system for small-scale urban aquaculture

This paper presents an innovative process to solve the nitrate build-up problem in recirculating aquaculture systems (RAS). The novel aspects of the process lie in a denitrification bioreactor system that uses solid cotton wool as the primary carbon source and a unique degassing chamber. In the latter, the water is physically stripped of dissolved gaseous O₂ (by means of a Venturi vacuum tube), and the subsequent denitrification becomes more efficient due to elimination of the problems of oxygen inhibition of denitrification and aerobic consumption of cotton wool. The cotton wool medium also serves as a physical barrier that traps organic particles, which, in turn, act as an additional carbon source for denitrification. Operation in the proposed system gives an extremely low C/N ratio of 0.82 g of cotton wool/g of nitrate N, which contributes to a significant reduction of biofilter volume. The additional advantage of using solid cotton wool as the carbon source is that it does not release organic residuals into the liquid to be recycled. Operation of the system over a long period consistently produced effluents with low nitrate levels (below 10 mg N/l), and there was only a very small need to replace system water. The overall treatment scheme, also incorporating an aerobic nitrification biofilter and a granular filtration device, produced water of excellent quality, i.e., with near-zero levels of nitrite and ammonia, a sufficiently high pH for aquaculture, and low turbidity. The proposed system thus provides a solution for sustainable small-scale, urban aquaculture operation with a very high recovery of water (over 99%) and minimal waste disposal.     

基于生物反应器制药废水中活的但非可培养状态细菌的分离

[目的]探究制药废水中活的但非可培养（viable but non-culturable,VBNC）状态细菌的组成与系统关系。[方法]利用土质滤材构建生物反应器,基于复苏促进因子（resuscitation promoting factor,Rpf）对 VBNC细菌的复苏刺激生长作用,采用 MPN （most probable number）法,稀释平板法分离其中复苏可培养化的 VBNC 菌株并解析其16S rRNA基因系统关系。[结果]在 MPN培养系中,Rpf对部分细菌有生长刺激作用。制药废水中存在对 Rpf敏感、复苏可培养化的 VBNC优势菌群;制药废水中对 Rpf敏感的 VBNC优势细菌主要有革兰氏阳性放线菌Microbacterium、Gordonia 和 Leucobacter 属近缘菌,革兰氏阴性菌 Candidimonas、Xanthobacter和 Aminobacter属近缘菌,其中菌株 ZYM1、ZYM3、ZYZR4和 ZYXR1可能属于新种。[结论]研究结果揭示了制药废水中存在 VBNC状态细菌,为研究其形成机理、复苏活性化机制以及制药废水的深度处理等提供重要的思路与方法。